The Intention.Apply RPC is quite large, so this PR attempts to break it down into smaller functions and dissolves the pre-config-entry approach to the breakdown as it only confused things.
Previously config entries sharing a kind & name but in different
namespaces could occasionally cause "stuck states" in replication
because the namespace fields were ignored during the differential
comparison phase.
Example:
Two config entries written to the primary:
kind=A,name=web,namespace=bar
kind=A,name=web,namespace=foo
Under the covers these both get saved to memdb, so they are sorted by
all 3 components (kind,name,namespace) during natural iteration. This
means that before the replication code does it's own incomplete sort,
the underlying data IS sorted by namespace ascending (bar comes before
foo).
After one pass of replication the primary and secondary datacenters have
the same set of config entries present. If
"kind=A,name=web,namespace=bar" were to be deleted, then things get
weird. Before replication the two sides look like:
primary: [
kind=A,name=web,namespace=foo
]
secondary: [
kind=A,name=web,namespace=bar
kind=A,name=web,namespace=foo
]
The differential comparison phase walks these two lists in sorted order
and first compares "kind=A,name=web,namespace=foo" vs
"kind=A,name=web,namespace=bar" and falsely determines they are the SAME
and are thus cause an update of "kind=A,name=web,namespace=foo". Then it
compares "<nothing>" with "kind=A,name=web,namespace=foo" and falsely
determines that the latter should be DELETED.
During reconciliation the deletes are processed before updates, and so
for a brief moment in the secondary "kind=A,name=web,namespace=foo" is
erroneously deleted and then immediately restored.
Unfortunately after this replication phase the final state is identical
to the initial state, so when it loops around again (rate limited) it
repeats the same set of operations indefinitely.
Extend Consul’s intentions model to allow for request-based access control enforcement for HTTP-like protocols in addition to the existing connection-based enforcement for unspecified protocols (e.g. tcp).
- Upgrade the ConfigEntry.ListAll RPC to be kind-aware so that older
copies of consul will not see new config entries it doesn't understand
replicate down.
- Add shim conversion code so that the old API/CLI method of interacting
with intentions will continue to work so long as none of these are
edited via config entry endpoints. Almost all of the read-only APIs will
continue to function indefinitely.
- Add new APIs that operate on individual intentions without IDs so that
the UI doesn't need to implement CAS operations.
- Add a new serf feature flag indicating support for
intentions-as-config-entries.
- The old line-item intentions way of interacting with the state store
will transparently flip between the legacy memdb table and the config
entry representations so that readers will never see a hiccup during
migration where the results are incomplete. It uses a piece of system
metadata to control the flip.
- The primary datacenter will begin migrating intentions into config
entries on startup once all servers in the datacenter are on a version
of Consul with the intentions-as-config-entries feature flag. When it is
complete the old state store representations will be cleared. We also
record a piece of system metadata indicating this has occurred. We use
this metadata to skip ALL of this code the next time the leader starts
up.
- The secondary datacenters continue to run the old intentions
replicator until all servers in the secondary DC and primary DC support
intentions-as-config-entries (via serf flag). Once this condition it met
the old intentions replicator ceases.
- The secondary datacenters replicate the new config entries as they are
migrated in the primary. When they detect that the primary has zeroed
it's old state store table it waits until all config entries up to that
point are replicated and then zeroes its own copy of the old state store
table. We also record a piece of system metadata indicating this has
occurred. We use this metadata to skip ALL of this code the next time
the leader starts up.
This adds a new very tiny memdb table and corresponding raft operation
for updating a very small effective map[string]string collection of
"system metadata". This can persistently record a fact about the Consul
state machine itself.
The first use of this feature will come in a later PR.
Whenever an upsert/deletion of a config entry happens, within the open
state store transaction we speculatively test compile all discovery
chains that may be affected by the pending modification to verify that
the write would not create an erroneous scenario (such as splitting
traffic to a subset that did not exist).
If a single discovery chain evaluation references two config entries
with the same kind and name in different namespaces then sometimes the
upsert/deletion would be falsely rejected. It does not appear as though
this bug would've let invalid writes through to the state store so the
correction does not require a cleanup phase.
During gossip encryption key rotation it would be nice to be able to see if all nodes are using the same key. This PR adds another field to the json response from `GET v1/operator/keyring` which lists the primary keys in use per dc. That way an operator can tell when a key was successfully setup as primary key.
Based on https://github.com/hashicorp/serf/pull/611 to add primary key to list keyring output:
```json
[
{
"WAN": true,
"Datacenter": "dc2",
"Segment": "",
"Keys": {
"0OuM4oC3Os18OblWiBbZUaHA7Hk+tNs/6nhNYtaNduM=": 6,
"SINm887hKTzmMWeBNKTJReaTLX3mBEJKriDyt88Ad+g=": 6
},
"PrimaryKeys": {
"SINm887hKTzmMWeBNKTJReaTLX3mBEJKriDyt88Ad+g=": 6
},
"NumNodes": 6
},
{
"WAN": false,
"Datacenter": "dc2",
"Segment": "",
"Keys": {
"0OuM4oC3Os18OblWiBbZUaHA7Hk+tNs/6nhNYtaNduM=": 8,
"SINm887hKTzmMWeBNKTJReaTLX3mBEJKriDyt88Ad+g=": 8
},
"PrimaryKeys": {
"SINm887hKTzmMWeBNKTJReaTLX3mBEJKriDyt88Ad+g=": 8
},
"NumNodes": 8
},
{
"WAN": false,
"Datacenter": "dc1",
"Segment": "",
"Keys": {
"0OuM4oC3Os18OblWiBbZUaHA7Hk+tNs/6nhNYtaNduM=": 3,
"SINm887hKTzmMWeBNKTJReaTLX3mBEJKriDyt88Ad+g=": 8
},
"PrimaryKeys": {
"SINm887hKTzmMWeBNKTJReaTLX3mBEJKriDyt88Ad+g=": 8
},
"NumNodes": 8
}
]
```
I intentionally did not change the CLI output because I didn't find a good way of displaying this information. There are a couple of options that we could implement later:
* add a flag to show the primary keys
* add a flag to show json output
Fixes#3393.
Fixes#8466
Since Consul 1.8.0 there was a bug in how ingress gateway protocol
compatibility was enforced. At the point in time that an ingress-gateway
config entry was modified the discovery chain for each upstream was
checked to ensure the ingress gateway protocol matched. Unfortunately
future modifications of other config entries were not validated against
existing ingress-gateway definitions, such as:
1. create tcp ingress-gateway pointing to 'api' (ok)
2. create service-defaults for 'api' setting protocol=http (worked, but not ok)
3. create service-splitter or service-router for 'api' (worked, but caused an agent panic)
If you were to do these in a different order, it would fail without a
crash:
1. create service-defaults for 'api' setting protocol=http (ok)
2. create service-splitter or service-router for 'api' (ok)
3. create tcp ingress-gateway pointing to 'api' (fail with message about
protocol mismatch)
This PR introduces the missing validation. The two new behaviors are:
1. create tcp ingress-gateway pointing to 'api' (ok)
2. (NEW) create service-defaults for 'api' setting protocol=http ("ok" for back compat)
3. (NEW) create service-splitter or service-router for 'api' (fail with
message about protocol mismatch)
In consideration for any existing users that may be inadvertently be
falling into item (2) above, that is now officiall a valid configuration
to be in. For anyone falling into item (3) above while you cannot use
the API to manufacture that scenario anymore, anyone that has old (now
bad) data will still be able to have the agent use them just enough to
generate a new agent/proxycfg error message rather than a panic.
Unfortunately we just don't have enough information to properly fix the
config entries.
A query made with AllowNotModifiedResponse and a MinIndex, where the
result has the same Index as MinIndex, will return an empty response
with QueryMeta.NotModified set to true.
Co-authored-by: Pierre Souchay <pierresouchay@users.noreply.github.com>